Continuous seiche in bays and harbors

Abstract. Seiches are often considered a transitory phenomenon wherein large amplitude water level oscillations are excited by a geophysical event, eventually dissipating some time after the event. However, continuous small-amplitude seiches have been recognized which raises a question regarding the origin of continuous forcing. We examine six bays around the Pacific where continuous seiches are evident and, based on spectral, modal, and kinematic analysis, suggest that tidally forced shelf resonances are a primary driver of continuous seiches.